William a



(No Model.)-

W. A. BALD-WIN. 'PROPELLER.

No. 470,097. PatentedMm. 1, 1892.

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Unirrno States ATENT Fries.

\VILLIAM A. BALDWIN, OF NEYV YORK, N. Y., A'SSIGNOR OF ONE-HALF TOROSWVELL D. SAIVYER, OF SAME PLACE.

PROPELLER.

SPECIFICATION forming part of Letters Patent No. 470,097,

dated March 1, 1892.

Application filed March 6, 1891. Serial No. 384.001- (No model.)

To ctZZ whom it may concern:

Be it known that I, WILLIAM A. BALDWIN, a citizen of the United States,residing at New York, in the county and State of New York, have inventedcertain new and useful Improvements in ater-Wheels or Propellers; and Ido declare the following to be a full, clear, and exact description ofthe invention, such as will enable others skilled in the art to which itappertains to make and use the same.

This invention relates to apropcller-wheel to be used on boats usingsteam or other motive power, and may be advantageously used inpropelling canal-boats.

The object of the invention is to utilize the full force of theresistance which the water will naturally afiord and get an increasedmotion without increasing the motive power by having each blade arrangedin a different path from its preceding one and successively reach outand out still water, or water which has not to any measure been agitatedby the blade arranged in advance of it. IVith this and other objects inView I have constructed a wheel or propeller in which a line drawnaround the shaft at the base of the blades would describe a spiral andanother line drawn over the tips of the blades would produce a similarfigure of greatly-increased diameter from the rear to the forward end ofthe shaft on which such blades are mounted.

The invention will be fully understood from the following descriptionand claim, when taken in connection with the annexed drawing, in whichthe figure is a side elevation of a part of the hull of a vessel,showing my improvements applied.

WVhile I have shown the interrupted screw or propeller applied to therear or stern of the keel, yet in some cases I may arrange one of suchpropellers on each side as well; but I do not wish to be understood asconfining myself to any number of propellers nor to any particular pointof location, but may use as many of themas the dictation of the mechanicor builder may suggest.

Referringby letter to said drawing, A indicates the hull of a vessel,which may. be of any ordinary or approved construction and B indicatesthe usual stern-post.

C indicates the shaft of my propeller. This shaft has its forward endbearingin the stern of the vessel, and its opposite end bearing in thestern-post, as shown, and may be connected with the drive-shaft of theboat in any suitable manner. The shaft 0 may be solid, and tapers fromend to end, the smaller end being directed forwardly. In some cases itmay be desirable to have a hollow sleeve or hub over the shaft, and insuch cases the bore of the hub or sleeve would be of a tapering orconical form, so as to firmly bear on the shaft throughout its length,and setscrews, bolts, and nuts or other suitable devices may beemployedfor removably or permanently .fixing the sleeve in position onthe shaft.

D indicates the paddles or blades, which may be of any desired lengthand width and are preferably provided with flat sides, as illustrated.These blades D increase in Width from their inner to their outer ends,whereby their inner portion will meet with but little resistance, andthey are given a slight twist, as shown, whereby their outer ends willrest approximately at right angles with respect to the shaft. The bladesof the first whirl b are of an equal length and width and arranged atequal distances apart in a spiral or helical manner, while the blades ofthe next succeeding whirl c are of a greater length and arranged,respectively, in a line with the longitudinally-disposed interspacesformed between the blades of the advanced or preceding set. The nextsucceeding set of blades are arranged on the shaftin a similarstaggering position and are of an increased length, so as to reach outinto andcut the still water, or water which has not been agitated by theblades ahead of them, and so on, increasing in length until the desirednumber of whirls or spirals have been made. In practice I should makefrom two to. four whirls, although more or less might be made, asdesired. propeller of this construction there is little or no lostmotion; The movement of the boat will be steady and forward and agreater speed will be had with a less amount of motive power, inasmuchas each and every blade With a boat equipped with a 5 will not enter thewater which has been violently agitated by its predecessor, but willsuccessively reach out and move in a path of still or undisturbed water,thereby meeting with resistance on but one side of the blades andavoiding any tendency to move in but one rotative direction.

Vhile I have described the blades as in creasing in length from theforward to the rear end of the shaft, yet it is obvious that when ashaft has a tapering cylindrical outer surface the blades may be ofequal length, and they would necessarily increase the diaaineter of thewhirls from front to rear of the shaft. In some cases it is notnecessary that care should be taken to have all of the blades of thesame length, as they may be made of unequal length and serveeffectively.

Having described my invention, what I claim, and desire to secure byLetters Patent, is-

A propeller for vessels, consisting of ashaft having an externalcylindrical surface taperin g from its rear to its forward end, theflatside twisted blades or paddles increasing in width from their innerto their outer ends and arranged in spiral series approximately at rightangles to the shaft, the blades of the spiral describing a largercircular area from front to rear of the shaft and arranged so that theblades of one Whirl will be in line with and approximately at rightangles to the longitudinally-disposed interspaces between the blades ofthe preceding whirl, substantially as specified;

In testimony whereof I affix my signature in presence of two witnesses.

WILLIAM A. BALDWIN. \Vitnesses:

CHAS. II. RAEDER, 'lHoMAs E. TURPIN.

